Start implement druid layout component

druid/extended/layout.lua

@@ -0,0 +1,100 @@
+-- Copyright (c) 2021 Maksim Tuprikov <insality@gmail.com>. This code is licensed under MIT license
+
+--- Layout management on node
+-- @module Layout
+-- @within BaseComponent
+-- @alias druid.layout
+
+---
+
+
+local const = require("druid.const")
+local helper = require("druid.helper")
+local component = require("druid.component")
+local Event = require("druid.event")
+
+---@class layout : druid.base_component
+local Layout = component.create("layout")
+
+
+function Layout:init(node, mode, on_size_changed_callback)
+    self.node = self:get_node(node)
+    self.origin_size = gui.get_size(self.node)
+    self.pivot = helper.get_pivot_offset(gui.get_pivot(self.node))
+    self.origin_position = gui.get_position(self.node)
+    self.position = vmath.vector3(self.origin_position)
+
+    gui.set_size_mode(self.node, gui.SIZE_MODE_MANUAL)
+    gui.set_adjust_mode(self.node, gui.ADJUST_FIT)
+
+    self._min_size = nil
+    self._max_size = nil
+
+    self.window_size = vmath.vector3(gui.get_width(), gui.get_height(), 0)
+    self.mode = mode or const.LAYOUT_MODE.FIT
+
+    self.on_size_changed = Event(on_size_changed_callback)
+
+    self:on_window_resized()
+end
+
+
+function Layout:on_window_resized()
+    local window_x, window_y = window.get_size()
+    local stretch_x = window_x / self.window_size.x
+    local stretch_y = window_y / self.window_size.y
+
+    local x_koef = stretch_x / math.min(stretch_x, stretch_y)
+    local y_koef = stretch_y / math.min(stretch_x, stretch_y)
+
+    local new_size = vmath.vector3(self.origin_size)
+    if self.mode == const.LAYOUT_MODE.STRETCH_X or self.mode == const.LAYOUT_MODE.STRETCH then
+        new_size.x = new_size.x * x_koef
+    end
+    if self.mode == const.LAYOUT_MODE.STRETCH_Y or self.mode == const.LAYOUT_MODE.STRETCH then
+        new_size.y = new_size.y * y_koef
+    end
+    if self._min_size then
+        new_size.x = math.max(new_size.x, self._min_size.x)
+        new_size.y = math.max(new_size.y, self._min_size.y)
+    end
+    if self._max_size then
+        new_size.x = math.min(new_size.x, self._max_size.x)
+        new_size.y = math.min(new_size.y, self._max_size.y)
+    end
+
+    gui.set_size(self.node, new_size)
+
+    self.position.x = self.origin_position.x * x_koef + self.origin_position.x * (1 - x_koef) * self.pivot.x * 2
+    self.position.y = self.origin_position.y * y_koef + self.origin_position.y * (1 - y_koef) * self.pivot.y * 2
+    gui.set_position(self.node, self.position)
+
+    self.on_size_changed:trigger(self:get_context(), new_size)
+end
+
+
+function Layout:set_min_size(min_size)
+    self._min_size = min_size
+    return self
+end
+
+
+function Layout:set_max_size(max_size)
+    self._max_size = max_size
+    return self
+end
+
+
+function Layout:set_origin_position(new_origin_position)
+    self.origin_position = new_origin_position or self.origin_position
+    return self
+end
+
+
+function Layout:set_origin_size(new_origin_size)
+    self.origin_size = new_origin_size or self.origin_size
+    return self
+end
+
+
+return Layout